Types 7820 + 7821

Evaluator / Evaluator Light

With Evaluator or Evaluator Light, measurement data can be edited and combined in order to calculate the rating level for a noise source, based on sound level meter measurement data. Evaluate and report on environmental noise based on sound level meter data.


To simplify the noise assessment, a variety of parameters are available that accord with national standards. Results are presented according to a framework of user-defined parameters, including time of the day/week as well as penalties for impulse and constant tones.


  • Calculation of rating levels according to national and international standards
  • Noise profile of industrial, residential, road and rail sound levels
  • Evaluation of noise in the environment against noise limits according to national and international standards

Using sound level meter Types 2250 or 2270 as a front end, Evaluator can record sound directly onto your PC's hard drive. The sound recordings are automatically merged into the measurements, marked in the profile display, and can be replayed directly from within this graph.

The PC-based software fully supports Sound Recording App BZ-7726 for Types 2250-Light, 2250 and 2270 sound level meters.

The software provides visualisation of your measured data as noise profiles (level versus time), spectra with 1/1- and 1/3-octave filters, as FFT spectra or as statistical displays of cumulative or level distributions. When viewing FFT spectra, a reference cursor, delta cursor, harmonic cursor and tone cursor is available, and you can overlay one spectrum with another for comparison.

Calculation of the rating level is based on a graphical profile you create from selected measurement contributions. Marker information is imported with the measurement data, and you can use the wizard to investigate data over a specified time to find and mark constant tones based on 1/3-octave measurements, impulse noise, the loudest period or all data above a certain level.


  • Direct import of data from sound level meters
  • Import of data from sound level meters using Measurement Partner Suite >BZ-5503
  • Dial-up modem data transfer and remote instrument control of sound level meter Types 2238 and 2260
  • Tonal Assessment to JNM2-1999, DIN 45 681-1992 and ISO/CD 1996-2-2001-05 using FFT spectra
  • Profile knitting to produce an overall rating level from different time-based contributions
  • Export of data as spreadsheets, text files and copy/paste into other documents